Women who took replacement progesterone after giving birth had decreased cravings to smoke and were more likely to stay off cigarettes, according to a new Yale study that assessed the use of progesterone as a treatment for postpartum smoking relapse.

The study, conducted by Ariadna Forray, MD, Assistant Professor of Psychiatry at Yale, found that progesterone treatment reduced smoking craving and slowed the rate of cigarette relapse in postpartum women.

Women who smoke often quit in pregnancy, when progesterone levels are high. Many relapse soon after delivery when progesterone levels drop.

The study, published in the journal Psychoneuroendocrinology, tested the effect of postpartum progesterone replacement in women with a history of pre-pregnancy smoking. Women taking progesterone were more likely to remain abstinent and took longer to relapse compared to women in the placebo group, according to the study, funded by the National Institute on Drug Abuse.

"These preliminary findings support the promise of progesterone treatment in postpartum smokers and could constitute a therapeutic breakthrough," the authors wrote.